1. Field of the Invention
The invention relates to a high voltage, air break disconnect switch and more particularly to a blade lock for a switch including an elongated blade which is rotated manually about its longitudinal axis and swung about a transverse axis when disengaging and engaging stationary jaws on a contact member.
2. The Prior Art
In previous switch units of this general type as exemplified by my U.S. Pat. No. 3,243,534, a safety lock for holding the blade in closed position consisted of a latch member mounted on the blade near the contact jaws on an axis parallel to the blade and thrust upwardly by a torsion spring. The end of the latch was formed with an upwardly open hook underlying engageable with a pin mounted on the contact block. The end of the latch was tapered downwardly so as to cause the latch to underride the terminal-mounted pin as the blade approached fully closed position and the end of the latch adjacent the blade was formed with a stop to limit upward movement of the outer end of the latch.
While this latch performs satisfactorily in most cases, if the insulator supporting the terminal is slightly tilted, the latch member might override the pin and thus not secure the blade in closed position.